text: Various corporate and government entities are researching the application of shear-thickening fluids for use as body armor. Such a system could allow the wearer flexibility for a normal range of movement, yet provide rigidity to resist piercing by bullets, stabbing knife blows, and similar attacks. The principle is similar to that of mail armor, though body armor using a dilatant would be much lighter. The dilatant fluid would disperse the force of a sudden blow over a wider area of the user's body, reducing the blunt force trauma. However, the dilatant would not provide any additional protection against slow attacks, such as a slow but forceful stab, which would allow flow to occur.
  In one study, standard Kevlar fabric was compared to a composite armor of Kevlar and a proprietary shear-thickening fluid. The results showed that the Kevlar/fluid combination performed better than the pure-Kevlar material, despite having less than one-third the Kevlar thickness.
  Four examples of dilatant materials being used in personal protective equipment are Armourgel, D3O, ArtiLage (Artificial Cartilage foam) and "Active Protection System" manufactured by Dow Corning.
  In 2002, researchers at the U.S. Army Research Laboratory and University of Delaware began researching the use of liquid armor, or a shear-thickening fluid in body armor. Researchers demonstrated that high-strength fabrics such as Kevlar can be made more bulletproof and stab-resistant when impregnated with the fluid. The goal of the “liquid armor” technology is to create a new material that is low-cost and lightweight while still offering equivalent or superior ballistic properties compared to current Kevlar fabric.
  For their work on liquid armor, Dr. Eric Wetzel, an ARL mechanical engineer, and his team were awarded the 2002 Paul A. Siple Award, the Army’s highest award for scientific achievement, at the Army Science Conference.
  The company D3O invented a non-Newtonian–based material that has seen wide adaptation across a broad range of standard and custom applications, including motorcycle and extreme-sports protective gear, industrial work wear, military applications, and impact protection for electronics. The materials allow flexibility during normal wear but become stiff and protective when strongly impacted. While some products are marketed directly, much of their manufacturing capability goes to selling and license the material to other companies for use in their own lines of protective products.